Those that jumped through all the hoops above bar, paid their dues in a messed up system where they bit their upper lip and got through it, and have been extremely frustrated at others trying to game the system.
When I heard the crowd roar every time Trump said “we’re going to kick them out” I knew exactly what the crowd was cheering. Trump never used those moments to say “but America is a nation of immigrants and we celebrate their contributions”. He wanted to rile up a crowd while maintaining a fig-leaf of “oh it’s only illegals who are evil”
You don’t have to have a PhD to understand the appeal and consequences of nativist populism — just the slightest understanding of history.